Stat 328 Lab #1 Key Summer 2000
(a) C œ 95.1124 = œ 0.000129
(b) Attached is a normal plot, histogram and some intervals for . and 5 made using JMP
4.0. The normal curve fitted on the histogram and the confidence intervals for . and 5
were added under the Fit Distribution menu. (In JMP-IN 3.2.6 you can get the normal
curve from the checkmark on the lower left corner of the report. I haven't figured out if
JMP-IN 3.2.6 will give the confidence interval for 5.)
(c) 95% Confidence interval for .: (95.1123,95.1124)
95% Confidence interval for 5: (9.013445 ‚ 10•& , 2.263865 ‚ 10•% )
(d) 95% prediction interval for a single additional observation: (95.1121,95.1127)
(e) The scale is inaccurate.
(f) The scale is precise.
(g) 99.99% and 93.55% respectively.
(h) T Ð[/312> • 111.2Ñ œ 0.16028
T Ð[/312> ž 111.2Ñ œ 0.12765
(i) T Ð[/312>Ñ • 113.2Ñ œ 0.25536
T Ð[/312>Ñ ž 113.2Ñ œ 0.070355
T Ð[/312> • 109.2Ñ œ 0.091947
T Ð[/312> ž 109.2Ñ œ 0.21127
(j) ! œ .16028 (from (h)!!)
(k) Yes. If 5 could be cut in half, 2.34% of complete consumer units will fail the final
inspection and 1.14% of consumer units missing the plastic bag will pass the final
inspection.
(l) T Ð[/312> • 123.47Ñ œ 0.01976
T Ð[/312> • 129.82Ñ œ 0.00089156
(m) $Þ!) œ
Ð"!%Þ%#€'Þ$&B•&Þ9#Ñ•"!%Þ%#
&Þ*'
Ê B œ $Þ)#
-1-
Untitled 1: Distribution
Page 2 of 2
3
.99
2
.95
.90
1
.75
.50
0
.25
-1
.10
.05
-2
.01
95.1121 95.1122
95.1123
95.1124
95.1125
95.1126 95.1127
Normal Quantile Plot
Distributions
y
Normal(95.1124,0.00013)
Fitted Normal
Parameter Estimates
Type
Parameter
Location Mu
Dispersion Sigma
Estimate Lower 95%
95.11236
0.00013
95.11228
0.00009
Upper 95%
95.11245
0.00023